fbc: fix #cmdline restart

- if cProgram() encountered a #cmdline directive requesting a restart
  then don't call fbMainEnd() - it doesn't make any sense to continue
  code generation if we know we are going to restart anyway
- related to combining command line options on the command line and
  command line options later encountered in #cmdline directives where
  some part of the user source is parsed and therefore code generation
  begins, but needs to abort and restart cleanly without trying to
  further generate code while tring to abort / restart.
- also related to '-z nobuiltins' specified on the command line with
  #cmdline to setting some options also.  This was causing an issue
  where fbc aborted with error instead of restarting the compilation
  due to fbc unable to complete the exit code normally.

src/compiler/fb.bas

@@ -1325,11 +1325,14 @@ sub fbCompile _
 
 	fbParsePreDefines()
 	fbParsePreIncludes()
+
 	if (fbShouldContinue()) then
 		cProgram()
 	end if
 
-	fbMainEnd( )
+	if (fbShouldContinue()) then
+		fbMainEnd( )
+	end if
 
 	'' compiling only, not cross-compiling?
 	if( fbGetOption( FB_COMPOPT_OBJINFO ) and _